Block #271,292

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 11/24/2013, 1:10:39 PM · Difficulty 9.9518 · 6,532,082 confirmations

TWN
Bi-Twin Chain

Interleaved pairs of primes that differ by 2, forming twin prime pairs at each level.

Block Header
Block Hash
59f60c2b66d25599f5f930d0bdba7b2de381d9bb56ba536527ee12eb22e98cad

Height

#271,292

Difficulty

9.951771

Transactions

6

Size

1.33 KB

Version

2

Bits

09f3a748

Nonce

35,514

Timestamp

11/24/2013, 1:10:39 PM

Confirmations

6,532,082

Merkle Root

45afd74034e248aa2dec9aeef6d30df7ff17c0b5cd9362e611fdf35937093625
Prime Chain Origin

This is the prime chain origin stored in the block header. It is a composite number (not prime itself) — it equals the first prime in the chain multiplied by a primorial. The origin anchors the entire chain to this specific block.

6.108 × 10¹⁰²(103-digit number)
61080428644002884882…49864135089255725999
Discovered Prime Numbers
Lower: 2^k × origin − 1 | Upper: 2^k × origin + 1

These are the actual prime numbers discovered by this block, computed using the verified Primecoin formula. Each number has been independently confirmed to pass the Fermat primality test. Use the FactorDB links to verify any number independently.

Level 0 — Twin Prime Pair (origin ± 1)
origin − 1
6.108 × 10¹⁰²(103-digit number)
61080428644002884882…49864135089255725999
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
6.108 × 10¹⁰²(103-digit number)
61080428644002884882…49864135089255726001
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: origin + 1 − origin − 1 = 2 (twin primes ✓)
Level 1 — Twin Prime Pair (2^1 × origin ± 1)
2^1 × origin − 1
1.221 × 10¹⁰³(104-digit number)
12216085728800576976…99728270178511451999
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.221 × 10¹⁰³(104-digit number)
12216085728800576976…99728270178511452001
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^1 × origin + 1 − 2^1 × origin − 1 = 2 (twin primes ✓)
Level 2 — Twin Prime Pair (2^2 × origin ± 1)
2^2 × origin − 1
2.443 × 10¹⁰³(104-digit number)
24432171457601153953…99456540357022903999
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.443 × 10¹⁰³(104-digit number)
24432171457601153953…99456540357022904001
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^2 × origin + 1 − 2^2 × origin − 1 = 2 (twin primes ✓)
Level 3 — Twin Prime Pair (2^3 × origin ± 1)
2^3 × origin − 1
4.886 × 10¹⁰³(104-digit number)
48864342915202307906…98913080714045807999
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.886 × 10¹⁰³(104-digit number)
48864342915202307906…98913080714045808001
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^3 × origin + 1 − 2^3 × origin − 1 = 2 (twin primes ✓)
Level 4 — Twin Prime Pair (2^4 × origin ± 1)
2^4 × origin − 1
9.772 × 10¹⁰³(104-digit number)
97728685830404615812…97826161428091615999
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
9.772 × 10¹⁰³(104-digit number)
97728685830404615812…97826161428091616001
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^4 × origin + 1 − 2^4 × origin − 1 = 2 (twin primes ✓)

What this block proved

The miner who found this block proved the existence of 10 consecutive prime numbers forming a Bi-Twin Chain. The prime chain origin — the large number shown above — anchors the chain and is divisible by a primorial (the product of small primes), cryptographically tying these prime numbers to this specific block.

★★☆☆☆
Rarity
UncommonChain length 10

Roughly 1 in 100 blocks. Solid but expected in a healthy network.

How Primecoin's Proof-of-Work Constructs These Primes

Primecoin stores a value called the prime chain origin in each block. The miner found a large integer such that when divided by a primorial (the product of small primes: 2 × 3 × 5 × 7 × …), the result is the first prime in the chain. The origin is deliberately divisible by this primorial — that divisibility is part of the proof.

Prime Chain Origin = First Prime × Primorial (2·3·5·7·11·…)
Source: Primecoin prime.cpp — CheckPrimeProofOfWork()

This is why the origin has many small prime factors — those factors are the primorial divisor. The chain then extends from the first prime using the TWN formula:

TWN: twin pairs (p, p+2) where p = origin/primorial − 1 and p+2 = origin/primorial + 1
Circulating Supply:57,671,028 XPM·at block #6,803,373 · updates every 60s
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